1. Field of the Invention
The present invention relates to liquid-cooled heat sink assemblies, and more particularly to a liquid-cooled heat sink assembly with a compact structure.
2. Description of Prior Art
Numerous modern electronic devices, such as computers, comprise electronic components mounted on circuit boards. When the electronic device operates, the electronic components can generate much heat. The heat must be removed from the electronic components; otherwise the electronic device may malfunction or even be damaged or destroyed.
Most electronic components are designed to operate over a wide range of temperatures. If the electronic component operates above its threshold operating temperature, it is liable to operate poorly or improperly. For example, the electronic component may operate too slowly, be less tolerant of voltage variations, be less tolerant of electrical “noise,” or fail prematurely.
One technique for removing heat is to a employ an air-cooled heat sink across contacts of the electronic component. However, due to the low density of air, the amount of heat that can be removed from the electronic component is limited. These days, electronic components such as integrated circuits incorporate more circuits, operate faster, and generate more heat than previously. The circulating air relied on by air-cooled heat sinks is often not sufficient to remove the heat generated by these modern electronic components, which are liable to exceed their threshold temperatures.
In order to overcome the above-described problems, an alternate means for removing heat employs a liquid which contacts a heat sink that is in contact with the electronic component. Because of their greater densities, moving liquids are capable of removing much greater amounts of heat than moving air. An example of this kind of liquid-cooled heat sink assembly is disclosed in China Patent No. 99,208,214. As shown in FIG. 4, the liquid-cooled heat sink assembly comprises a pump 100, a heat sink 400 defining a chamber therein and a heat exchanger 300 having a cooling wafer 200. A zigzagged passageway 403 is defined in the chamber of the heat sink 400 by a plurality of parallel partitions, for liquid coolant to flow therealong. The pump 100 defines a first inlet 102 and a first outlet 101. The heat exchanger 300 defines a second inlet 302, and a second outlet 301 connecting with the first inlet 102 of the pump 100. A pipe 405 connects an inlet of the heat sink 400 and the first outlet 101 of the pump 100. An outlet of the heat sink 400 is connected to the second inlet 302 of the heat exchanger 300 through another pipe 406. Thus, the heat sink 400, the pump 100 and the heat exchanger 300 together form a circuit for transferring heat from an electronic component to the liquid coolant contained in the circuit and for dissipating the heat at the heat exchanger 300.
However, in the above-described liquid-cooled heat sink assembly, the heat sink 400, the heat exchanger 300 and the pump 100 are separated from each other. This makes the structure of the liquid-cooled heat sink assembly unduly complicated and heavy, and difficult to position among electronic components in a typical electronic device.
Thus, an improved liquid-cooled heat sink which overcomes the above-mentioned problems is desired.